The First Choice for Water Vapor Permeability Test of Drug Packaging-Weighing Method

Abstract: Test methods of water vapor permeability test of drug packaging and the data relationship of various test methods, the relationship between and developmental direction of weighing method and desiccant method.

Water vapor permeability is an important index in evaluating barrier property of materials and is no less important than auto gas permeability. Water vapor permeability can be tested with weighing method or sensor method. Weighing method, or cup method, is the basic method, while test data of sensor method should be calibrated by the data of cup method (including infrared method, dynamic relative humidity method and electrolytic method). Because the uniform data system of weighing method is adopted, data comparability of various methods becomes rather good. In 2003, the state Drug Administration issued YBB00092003 Water Vapor Permeability Measurement, which includes the first method cup method, the second method electrolytic method and the third method weight method. Among that, the first and the second methods are applicable to film, sheets and aluminum foil of drug packaging. The third method applies to drug container packaging.